Buffing machine



Oct. 27, 1942. e. F. WIKLE BUFFING MACHINE Filed Oct. 17, 1940 3 Sheets-Sheet 1 INVENTOR. GEORGE ff W/AAE v I ATTORNEY Oct. 27, 1942. G. F. WIKL E BUFFINGV MACHINE 3 Sheets-Sheet 2 Filed Oct. 17, 1940 if I ' INVENTOR. 6150565 F.

A rronmaY \BUFFING MACHINE Filed Oct. 1940 s Sheets-Sheet s INVENTOR. 6.60565 f. (W/(Z5 BY Q i Q E ATTORNEW Patented Oct. 27, 1942 BUFFING MACHINE George F. Wikle, Detroit, Mich., assignor to United States Rubber Company, New York, N. Y., a corporation of New Jersey ApplicationOctober 17, 1940, Serial No. 361,531

' 1 Claim.

This invention relates to buffing machines and more particularly relates to bufiing machines adapted for processing relatively wide elongated sheets or strips of relatively soft yieldable vul- This buffing or roughening is necessary in order to obtain a secure integral union between these surfaces of cured stock during the subsequent vulcanizing operation. Heretofore, in cases where such buffing of the cured stock was performed manually and particularly where this stock comprised relatively large sheets or elongated strips of material, much time and effort was required and much difficulty experienced in obtaining the complete and uniform results desired over the entire surface or surfaces of the rubber composition; and in cases where these relatively large sheets or strips were of considerable thickness and formed from very soft and yieldable vulcanized rubber composition it was found to be most difficult to handle and prepare the material properly and without injury thereto.

The bufling machine of the present invention substantially eliminates these and other objectionable conditions encountered heretofore by providing means for automatically and continuously feeding sheets or strips of vulcanized rubher composition through the machine at a uniform predetermined speed while engaging and holding successive portions of the material in proper position as the bufling operations are performed thereon. Convenient and quickly adjustable means are also provided for accommodating sheets or strips of rubber composition of various thicknesses and hardnesses passing through the machine. The machine is so constructed and arranged that its operation is immediately subject to thecontrol of the operator and automatic safety means is provided to function in cooperation therewith for preventing injury to the operator during operation of the machine.

The invention will bemore readily understood from the following description when taken in conjunction with the accompanying drawings,

in which:

Fig. 1 is a side elevational view showing a preferred embodiment of the invention;

Fig. 2 is a plan view of the bufilng machine of Fig. l; and, n

Fig. 3 is an enlarged view, partly in section and partly brokenaway, of the details of a por tion of the machine shown in Fig. 1.

Referring to the drawings in detail and in particular to Figs. 1 and 2, the reference nu- 'meral l0 indicates generally a main frame upon the top of which is carried a secondary frame H in spaced relation therewith. Carried upon spaced upper side bars I2 and E3 of the main frame If] is a rotatably mounted shaft l4 upon which is keyed or otherwise secured, between the side bars l2 and IS, a relatively wide work-supporting drum I5. Upon the outer surface of this drum [5 is secured a relatively thick soft covering layer of rubber composition It; the cushioning and anti-slip purposes of which will be more fully hereinafter described. Power means, in the form of a conventional electric motor I! and reduction gearing [8 attached upon the side of the main frame 10, and a system of chains and sprockets generally indicated by the numeral I!) serve to drive the shaft M at a comparatively slow but positive and uniform rate of speed.

The secondary frame H, which comprises spaced side bars 2| and 22 interconnected by transverse angle bars 23 and 24, is supported along its rear edge by flat metallic plates 25 rigidly secured, in any suitable manner, such as by welding, to the bar 24 and to an upper transverse member at the rear of the main frame in so as to flex slightly and allow a limited amount of vertical adjustment of the forward end of the secondary frame relative to the main frame It]. This adjustment is effective through'the means of a pair of vertically extending threaded rods 26 and 21 which are positioned at opposite sides of the machine and have their opposite ends located in openings in the side bars l2 and I3 of the main frame Ill and in the side bars 2! and 22 of the secondary frame II, respectively. These rods 26 and 2? are provided with suitable clamping nuts on opposite sides of each of the said side bars so that exact increments of adjustment of the forward end of the secondary frame relative to the main frame may be easily and quickly obtained by the operator of the machine when desired. The purpose-of this adjustment is to accommodate strips or sheets of material of var ious thicknesses being fed through the machine.

A relatively Wide bufling wheel 3!, preferably in the form of circular wire brushes, sanding drums, or the like, is clamped or otherwise removably secured upon a shaft 32 for rotation therewith in supporting bearings 33 and 34 upon the side bars 2| and 22, respectively, and is connected to a conventional electric motor 35 by a multiple V-belt drive generally indicated by the numeral 35. This motor is adjustably mounted upon a supporting plate 31 carried by the transverse angle bars 23 and 24 of the secondary frame in any well known manner.

Referring in detail to Fig. 3, it will be seen that when a wide flat strip of sheet material 40, such as soft yieldable vulcanized rubber composition, is fed onto the rubber covered drum I rotating slowly in the direction of the arrow A, the material will be carried by the drum into the bite region 4| between the buffing wheel SI and the drum l5. The buffing wheel 3| rotates in the direction indicated by the arrow B but at a speed much greater than the speed of the drum l5. Since the normal tendency of the fast moving wheel 3| is to drag the strip material 40 rapidly through the machine suitable means is provided to prevent such a condition, which means is in the form of a wide steel pressure roll 42 positioned adjacent and in parallel relation to the drum l5 and rotatably carried by a. pair of bellcrank levers 43 suitably mounted upon a transverse shaft 44 mounted in the side bars |2 and i3 at opposite sides of the main frame 553. The pressure roll 42 is intended to bear against the upper surface of the strip material resting upon the drum l5 and to hold this material in contact with the soft rubber covering IQ of this drum as the material is fed into the bite region 4| between the wheel 3| and the drum l5. The roll 42 is of a comparatively small diameter and positioned near the bite region 4| so that'the material will be correctly guided and controlled as it enters this region. By locating the roll 42 near the bite region it is possible to properly buff the strip or sheet material closer to the rear edge thereof than would be possible otherwise. 'A pair of coil springs 45 at opposite sides of the machine are connected to the free ends of the levers 43 and to a fixed upwardly extending portion of the main frame It so that a constant pull will-be exerted upon these levers which tends to elevate the pressure roll above the drum l5.

Manually controlled means in the form of a hand crank 46 mounted upon a transverse shaft 41 mounted in the upwardly extending portion of the main frame |fi serves to actuate a pair of slightly eccentric earns 48 carried near the opposite ends of the shaft so as to force the levers 43 and thus the pressure roll 42 into operative position against the material 4 upon the drum 5. A pair of bolts 49 threaded into intermediate parts of the bell crank levers 43 serve to adjustably vary the operative position of the pressure roll 42 depending upon the thickness, and other physical properties such as hardness, of the particular vulcanized rubber strip material being fed through the machine. Lock nuts 58 shown upon the bolts 49 are employed for holding the bolts in proper adjusted position.

Also shown in Fig. 3 is a safety control device for preventing injury to the operator of the machine, such as having his fingers accidentally caught between the drum I5 and the pressure rolls 42 while attempting to start a new strip of material through the machine. This device comprises a guard plate 5| normally positioned closely adjacent the surface of the drum I5 and of the drum. This guard plate has its opposite ends welded or otherwise secured to a pair of levers 52 fixedly mounted upon a shaft 53 pivotally carried in apertures in upwardly extending portions of a pair of brackets 54 and 55 secured upon the side bars 2| and 22 of the secondary frame I I. A cam 56 integrally carried upon a top of one of the levers 52 is so located as to engage a roller 51 extending from the bottom of an electric safety switch 58 positioned upon a side of the upwardly extending portion of the bracket 54. Bolts 59, or similar securing means, extend through slots. 60 in the bracket 54 and allow for proper adjustment of the switch 58 and thus the roller 5'! relative to the cam 55. Arms 6|, arranged to extend downwardly from the brackets 54 and 55, are provided with inwardly projecting lugs l 62 arranged to serve as limiting means or stops sufficient width to extend the entire length of 7 for preventing downward swinging movement of the guard plate 5| beyond its normal operative position shown in Fig. 3.

Anelectric switch 63 (Fig. 1), of a conventional type having starting and stopping buttons, is provided upon the front of the main frame In, for

controlling the electric motor 1 driving the drum I5. The electric safety switch 58, previously referred to, is connected in series with the switch 53 and the motor I! for instantly stopping the motor when this electric circuit (not shown) is interrupted.

It will be seen from the foregoing description that during the operation of the safety device, even the slightest pivotal movement of the guard plate 5| upwardly and rearwardly about the shaft 53 by the hand of the operator will cause the cam 56 to elevate the roller 51 and thus actuate the switch 58; immediately stopping the motor I! and the supporting drum l5. With the parts of the safety device so constructed and arranged, it will be apparent that it is practically impossible for the operator of the machine to become injured while feeding stock material onto the drum I5.

An additional electric switch 64, similar to the switch 63, is located upon the front of the main frame l0 and is connected to the motor so as to place the operation of this motor conveniently under the control of the operator of the bufmg machine.

When it is desired to operate the bufiing machine of the present invention, the rotation of the drum l5 and the buffing wheel 3| is started by pushing the starting buttons on the switches 53 and 54 respectively. The control handle 45 is then moved to the dotted line position shown in Fignl; which action releases the levers 43 and allows the'spring 45 to retract the pressure roll 42 SllfilCiGIltlY to allow the strip material 4t to be fed or drawn between the roll 42 and drum l5.

The pressure roll 42 is then applied against the strip by swinging the lever to its heavy line position. It will be noted that the forward edge of the side bar l2, or the bracket 54 carried thereon, serves to limit the rearward swinging movement on the handle 46. When stock of a slightly different thickness is supplied to the machine the bolts 49 may be adjusted slightly to care for such changes before the operation of the machine is commenced.

It has been found in actual practice desirable to stop the buffing wheel 3| from rotating just before the last and of the strip or sheet of rubber colnposition passes from beneath the roll 42, so that the strip will not be pulled into and piled up in the bite region 4| by the rapidly moving wheel 3| and thus injure the stock or possibly parts of the machine as well.

The use of the comparatively thick soft layer l6 of rubber composition on the drum i5 has several advantages. The relatively high coeflicient of friction between the strip material and the drum covering prevents relative slipping between the material and the drum under the dragging influence of the wheel 3 I. This thick layer [6 also yields under the pressure of the roll 42 and affords a wider area of contact for this roll, thus allowing the use of greater pressures upon the material without injury to the material. Yielding of the layer I6 also produces a somewhat wider or greater area in contact with the buffing wheel at any given time.

Thus it will be seen that I have provided a buffing machine which will easily, quickly and substantially automatically roughen or buif wide strips of soft vulcanized rubber composition, or

other similar strip material, in an efficient, complete and uniform manner.

Although the invention has been disclosed in connection with the specific details of a preferred embodiment thereof, it will be readily understood that such details are not intended to be limitative of the invention exceptinsofar as is set forth in the accompanying claim.

Having thus described my invention what I claim and desire to protect by Letters Patent is:

A machine for bufling elongated strips or sheets of relatively soft yieldable material comprising in combination a main frame having a Worksupporting drum rotatably mounted thereon, a presser roll mounted on said frame for holding sheets of material on the drum, independent driving means for rotating said drum supported on said frame, a secondary frame above the main frame, a bufling wheel rotatably supported in the secondary frame adjacent one end thereof, independent driving means supported by the secondary frame for rotating the buffing Wheel, relatively rigid slightly bendable means support ing the opposite end of the secondary frame and connecting said opposite end to the main frame whereby the weight of said buffing wheel and its driving means will constantly urge said buffing wheel towards the work-supporting drum, and an adjustable support for supporting the first mentioned end of the secondary frame upon the main frame and for limiting the approach of the buffing wheel toward the work-supporting drum.

GEORGE F. W'IKLE. 

